Add Text to PDFs
with a Simple API
Easily add and map fields to your PDF documents using a clean and reliable developer API.
Works Seamlessly With Your Favorite Tools
Our API connects effortlessly to automation platforms, CRMs, and spreadsheet tools.
Fast, Secure & Developer-Friendly
Everything you need to generate PDFs programmatically—without code or storage headaches.
In-Browser Editor
Visually map text, tables, and form fields directly on your PDF templates with our intuitive editor—no technical skills needed.
Dynamic Data via API
Insert text, tables, and prefill form fields into templates using simple HTTP API calls. Receive binary PDFs instantly.
Copy-Paste Integration
Quickly connect your app with ready-to-go HTTP examples. Works seamlessly with cURL, Postman, Zapier, and more.
Custom Watermarking
Apply dynamic text watermarks with full control over position, font, rotation, opacity, and color for branding or security.
Form Field Extraction
Automatically detect and extract all form field names from your uploaded PDF templates via API, simplifying data mapping.
Flexible Credit System
Our pay-as-you-go model means credits never expire. Only pay for the API calls you make, ensuring cost-efficiency.
Data Privacy & Security
We only store your templates. All input data and generated files are immediately deleted after API calls, ensuring your data privacy.
High Reliability & Speed
Built for performance with 99.8% uptime and a high success rate. Get fast, reliable PDF generation you can trust.
How It Works
Generate customized PDFs with a few clicks—no complex setup, no storage needed.
Upload Your PDF
Create a template by uploading your PDF. This is the only thing we store on our end.
Map Fields
Use our in-browser editor to visually map text and table fields onto your template.
Call the API
Send data via API to insert content into the template. You'll receive a final PDF file instantly.
API Dashboard Overview
Monitor your usage, manage templates, and track every API call—all from a single, secure dashboard.
- View your subscription and credit usage
- Track recent API requests and their statuses
- Search and organize your PDF templates
- Manage API keys and template settings
Privacy & Data Security
Your data never touches our storage—only your templates stay with us.
🔒 Maximum Privacy by Design
We do not retain or store any API-generated files. Templates are the only assets stored, giving you full control of file delivery and storage on your end.
Your Privacy First
We never store any data or files from API requests. You have full control of where your documents go.
Templates Only
We only store your uploaded templates for reuse. Generated files are streamed back and never saved.
No File Storage
Generated PDFs are returned immediately via API response. Nothing is retained on our servers.
Simple, Transparent Pricing
Our flexible credit system means you only pay for what you use — with no surprises.
How Credits Work
Purchase credits and use them for various API calls — no monthly commitment required.
Current rate
$1 = 50 credits
Example costs
- 1 credit = 1 Prefill API call
- 2 credits = 1 Watermarking API call
Why Choose Credits?
- Pay-as-you-go — no subscription required
- Credits never expire
- 1000 API calls limit
- 1 credit = 1 Prefill API call
- 2 credits = 1 Watermarking API call
- Works with all templates & features
- Transparent usage tracking
- Not billed for failed calls
Simple API Integration
Add text, tables, and prefill form fields in your PDF templates with one secure HTTP request.
curl -X 'POST' \
'https://api.prefillpdf.com/fill-pdf' \
-H 'accept: application/json' \
-H 'Authorization: Bearer YOUR_API_KEY_HERE' \
-H 'Content-Type: application/json' \
-d '{
"template_id": "your-template-id-123",
"data": {
"customerName": "Jane Doe",
"invoiceNumber": "INV-2025-001",
"totalAmount": "$500.00"
},
"form-fields": {
"customer_name_field": "string",
"invoice_number_field": "string",
"total_amount_field": "string",
"date_field": "string"
}
}' Built for Developers
Our API delivers fully filled PDFs directly in the response—no temp links or file storage involved. Just send your data and get a binary back instantly.
- RESTful JSON API with simple POST requests
- Copy-paste ready examples for instant integration
- Secure authentication via API key headers
- Returns a binary PDF directly—no storage on our side
- Optimized for speed and 98.2%+ success rate
- Extract form fields from templates
- Prefill form fields with dynamic data
Try It Out - Free Demo
Upload your PDF and see how easy it is to add fillable fields
Drag & drop your PDF here
or click to browse files
🔒 Privacy guaranteed: Demo files are automatically deleted after 5 minutes. No account required.
Ready to Simplify Your PDF Workflows?
Start adding text to your PDFs programmatically today.